From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id C54793F075D; Mon, 17 Aug 2026 14:03:41 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786975423; cv=none; b=kN8MCq43DuOt8Jjh5beqwA5J0SGMdLE3YTxYjY7xOEgtHNMMRfLzm6/Vej4rBdPFecPRdzxf9NdRPR+JU35kP+FaiaBxQDtm99BRqnwT4M6w62vqUi1giP5L8ZNZiiPsKGG6UfwsKv4hJEl4kS9Xb/lSB+X1aTVtpZdjjHAJy9c= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786975423; c=relaxed/simple; bh=E+fk+AlH9P8LNrNP/EcKzQXpjpBLcPqZ6qbOytTbjpU=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=EbN+ZTejM9WkSsYymhjVg13vZIzcqyy1sjs0FE8LdINYsN4Kc76D+P/TDRWrInleD24i/u1uvQ0ucxaJNrdsv97Xe6U3VbLCLM2hFEZvZ0Ns3a0NfUs2bNPmVENLlZDyLCUk4b8Bu00I6JWwvJhTI+fSlQzDL8UhTMPsYN1hF3s= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=wUdS460e; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="wUdS460e" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1A8B71F000E9; Mon, 17 Aug 2026 14:03:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1786975421; bh=kWNWLdMvOYafu/Mboa/WdQ0GXk1HSeZP25lTa/kbBtU=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=wUdS460eaErhcjs+n4oVbmxlKDTh0ok3BoGwOZVHthJ0dbICKWo6rq5L5V8sDOm7v WBYCA6Cd7eUpIYX36JjQ+nBG4WtylgB8U5rtGd0607LMaVu7j8GnMxW+i/775kMJSc mBvlAHz17MnrbgMdGd2jzGvxiHAv9vDgBL475lvE= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Daehyeon Ko <4ncienth@gmail.com>, Sabrina Dubroca , Paolo Abeni , Sasha Levin Subject: [PATCH 5.10 003/389] macsec: dont read an unset MAC header in macsec_encrypt() Date: Mon, 17 Aug 2026 15:27:22 +0200 Message-ID: <20260817132538.952347955@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260817132538.796021292@linuxfoundation.org> References: <20260817132538.796021292@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 5.10-stable review patch. If anyone has any objections, please let me know. ------------------ From: Daehyeon Ko <4ncienth@gmail.com> commit f5089008f90c0a7c5520dff3934e0af00adf322d upstream. macsec_encrypt() reads the Ethernet header via eth_hdr(skb) (skb->head + skb->mac_header) to memmove() the 12 source/destination MAC bytes forward and make room for the SecTAG. On the AF_PACKET SOCK_RAW + PACKET_QDISC_BYPASS transmit path the skb reaches the macsec ndo_start_xmit() with the MAC header unset, so eth_hdr(skb) resolves to skb->head + (u16)~0 and the read is out of bounds: a 12-byte heap over-read that is also emitted on the wire as the frame's outer source/destination MAC. KASAN reports a slab-out-of-bounds read in macsec_start_xmit() on 6.0; on current mainline a CONFIG_DEBUG_NET build flags it as an unset mac header in skb_mac_header(). On the TX path the L2 header is at skb->data, so use skb_eth_hdr(), added by commit 96cc4b69581d ("macvlan: do not assume mac_header is set in macvlan_broadcast()") for exactly this purpose. Fixes: c09440f7dcb3 ("macsec: introduce IEEE 802.1AE driver") Cc: stable@vger.kernel.org Signed-off-by: Daehyeon Ko <4ncienth@gmail.com> Reviewed-by: Sabrina Dubroca Link: https://patch.msgid.link/20260703083634.2035145-1-4ncienth@gmail.com Signed-off-by: Paolo Abeni Signed-off-by: Daehyeon Ko <4ncienth@gmail.com> Signed-off-by: Sasha Levin --- drivers/net/macsec.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/net/macsec.c b/drivers/net/macsec.c index d19b5b1c1aca11..d07dba76940a9d 100644 --- a/drivers/net/macsec.c +++ b/drivers/net/macsec.c @@ -666,7 +666,7 @@ static struct sk_buff *macsec_encrypt(struct sk_buff *skb, } unprotected_len = skb->len; - eth = eth_hdr(skb); + eth = skb_eth_hdr(skb); sci_present = send_sci(secy); hh = skb_push(skb, macsec_extra_len(sci_present)); memmove(hh, eth, 2 * ETH_ALEN); -- 2.53.0